Mining projects in the UK and the community

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Created: Friday, 21 April 2023 08:50

Written by D. Tudor

The three major mining projects currently under way in the UK involve rail, coal, and fertilizer. They are all at various stages of the project cycle.

HS₂, the controversial high-speed rail project, was originally envisaged to connect London to Manchester and Leeds via Birmingham by 2033. Economics and politics have had a major impact on the final cost – up from an initial £35 billion to over £100 billion, and on the final route – the Birmingham Leeds link has been scrapped. However, work goes on and HS2 has once again begun tunnelling under London after launching its third giant tunnel boring machine (TBM) near Euston station. Following a longstanding tradition of naming TBMs after women, members of the local community have selected the name ‘Lydia’ for the TBM. Lydia Gandaa is a former teacher at the nearby Old Oak Common Primary School and a founding member of the Bubble & Squeak social enterprise in the area. She is an active member of the local community, running after-school and holiday clubs at the Old Oak Community Centre.

The new coal mine in Cumbria is a project near Whitehaven that will produce 2.8 million tons of coking coal a year for steelmaking and create 500 new jobs. It was approved by the UK government in January 2023, despite objections from local, national, and global groups over its climate impact. The mine will emit about 9 million tons of greenhouse gases a year, equivalent to putting 200 000 cars on the road. Most of the coal mined will be exported. The UK Climate Change Committee condemned the decision and said it contradicted the global effort towards net zero. Climate campaigners have been denied the opportunity to institute a legal challenge against the government over its decision to grant planning permission for a new coal mine in Cumbria. The project was initially approved by Cumbria County Council in October 2020. West Cumbria Mining, the firm behind the project, promised to create 500 direct jobs and 1500 in the wider community.

The Woodsmith project is Anglo American’s new polyhalite fertilizer mine that is being developed in the northeast of England near Whitby. Polyhalite is a naturally occurring mineral that contains potassium, sulphur, magnesium, and calcium plus numerous micronutrients, making it an ideal natural fertilizer. The project is currently sinking two mine shafts over a mile deep near Sneaton, south of Whitby and a 37 km long tunnel to a processing area at Wilton on Teesside.

After an investment of £400 million in 2022, Anglo announced that the capital expenditure for this year will be £650 million and approximately £800 million per year for the following three years – a significant investment for the local area.
The project currently employs over 1650 people at its sites in Whitby, Teesside, and Scarborough, with the majority being from the local communities.

The Woodsmith Foundation is an independent charity funded by Anglo American and has recently awarded grants totalling almost £250 000 towards initiatives that will support local communities from Teesside to Scarborough.
Seventy organizations received grants from the Foundation to help them deliver a range of programmes. For example, Scarborough Pride will use their grant to offer meaningful support and activities for the LGBT+ community in the Scarborough Borough. The Loftus Town Council will use their grant to start a gardening club for residents.

So, mining and the community are inseparable. What happens when lithium mining starts in Cornwall will be another story!

D. Tudor

The Competent Person

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Created: Monday, 13 March 2023 07:56

Written by S.M. Rupprecht

The SAMREC Code (2016) defines a Competent Person as one having a minimum of five years of relevant experience in the style of mineralization or type of deposit under consideration. In addition, a Competent Person must be registered with a professional organization (SACNASP, ECSA, SAGC) or a member or a fellow of a learned society (GSSA, SAIMM, IMSSA) or Recognised Professional Organisation (RPO). These bodies have enforceable disciplinary processes, including the power to suspend or expel a member.

In recent years, the role of the Competent Person has undergone scrutiny regarding the quality of work being presented and whether Competent Persons are overstating their level of relevant competency. Some of the problems identified are as follows:

• Incorrectly claiming relevant competency in a deposit type or situation under consideration
• Poor application of Reasonable Prospects of Eventual Economic Extraction (RPEEE) to justify Mineral Resource classification, and improper classification of Mineral Resources
• Documentation of overly optimistic mining schedules, estimation of capital expenditure, and operating costs
• Overly technically worded technical reports inclusive of sale pitches, unrealistic, or misleading statements;
• Poor reporting of Environmental, Social, and Governance (ESG) issues
• Failure to communicate risks related to mineral deposits and projects adequately and clearly
  Failure to use multidisciplinary technical specialists to improve the quality of the technical report.

Self-assessment of relevant competency is important and is also connected to ethical considerations. Competent Persons must be clearly satisfied in their own minds that they can face their peers and demonstrate competency. The investment community is seeking transparency from Competent Persons, with many calling for the inclusion of detailed CVs to demonstrate a Competent Person’s relevant experience.

The application of RPEEE can widely vary between Competent Persons. The Competent Person must consider the geoscientific knowledge and the modifying factors, both technical and economic aspects. The establishment of RPEEE demands an Initial Assessment, not simply an inventory of mineralized material above a stated cut-off grade.

The application of modifying factors in technical studies is critical. The Competent Person must ascertain that the inputs used in technical studies are appropriate and not overly optimistic. It is recommended that technical specialists assist Competent Persons in ensuring all technical inputs are appropriate and realistic, and the associated risks are highlighted. Key inputs include ramp-up schedule, development rates, estimation of mining loss and dilution (i.e. estimation of ROM grade), metallurgical recovery factors, price assumptions, operating and capital cost estimates, economic evaluation, and risk identification.

The Competent Person must employ the plain English principle to improve the readability of technical reports so as to benefit investors who lack a scientific background. Other technical reports can be written in such a manner that they resemble a prospectus rather than a technical report. In some cases, material misstatements, omissions, and misrepresentation can occur, either by accident or deliberately. The Competent Person must be diligent in investigating and reporting all material aspects and must conduct sufficient examinations to ensure conditions are as reported by the project owner or registrant. What may not be a ‘big deal’ to an owner may be material to an investor. Competent Persons must ensure they are not unduly influenced by project owners.
ESG issues have become relevant due to the increasing global awareness of human beings’ impacts on our planet. Under the SAMREC Code, ESG issues are considered fundamental contributors to Modifying Factors that play an essential role in determining RPEEE for Mineral Resources and the declaration of Mineral Reserves.

It is important to note that all projects embody risk; therefore, Competent Persons must ensure all material risks are identified and discussed. The days of a single or two-person Competent Persons team are of the past; technical reports require several specialists that should sign off on their specific areas of expertise.

Promoting continuous professional development to ensure Competent Persons are knowledgeable about current reporting trends remains paramount. This is especially important for Competent Persons on operations which may not have internal training programmes.

In the end, Competent Persons must use their professional judgement in providing adequate disclosure of all material aspects, bearing in mind that the ‘Competent Person must be clearly satisfied in their minds that they can face their peers and demonstrate competence’ (SAMREC, 2016).

Competent Persons must demonstrate a level of ethics. The author is reminded of a quote from Theodore Roosevelt – ‘Knowing what’s right doesn’t mean much unless you do what’s right’. Knowing the SAMREC Code is not enough; one must also abide by it.

S.M. Rupprecht

The value of clear communication in an increasingly complex world

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Created: Saturday, 28 January 2023 06:30

Written by Q.G. Reynolds

As a reader of the SAIMM Journal, you might well know that the mining and metallurgical engineering industry is one of the most complex and intricate of human endeavours. This edition’s excellent set of papers particularly demonstrates that successful enterprises routinely collaborate across disciplines. Advanced technical research and development stakeholders need to interact with economic and business entities while also considering environmental sustainability, social ethics, and corporate governance. In addition to this, the industry has become truly global, with experts from a broad array of cultural and social backgrounds, sharing knowledge via the written word.

Therefore, one of the most critical skills in our industry is the ability to clearly communicate difficult concepts between different fields of expertise. When communication is done well, it can be agile and effective with minimal oversight, even in challenging time-critical workflows; without it, misunderstandings and wasted effort are the order of the day. One way to ensure that this communication is done well, is through the use of plain language principles.

The drive to adopt plain language principles is gathering momentum in many areas where large and diverse teams execute highly cross-disciplinary projects (one example is https://www.plainlanguage.gov/guidelines/). Plain language aims to improve clarity and reduce ambiguity. In particular, it can aid with the communication of information out of pockets of expertise where domain-specific jargon and terminology often obscure the core ideas. Perhaps it’s time we looked at it for our world?

Q.G. Reynolds
Pyrometallurgy Division, Mintek
Process Engineering Department, Stellenbosch University

The future of coal

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Created: Monday, 12 September 2022 07:42

Written by H. Lodewijks

Coal has recently gone through a revival, with demand and prices internationally at levels not seen in years. It is obviously uncertain for how long this trend will persist, but it does illustrate the pitfalls of trying to forecast demand for fossil energy in times of uncertainty. It seems clear that coal as an energy source will be largely phased out in the medium to long term, but it is clearly in demand in the short term. In the meantime, a lot of work needs to be done to complete the transition to renewable energy, and this Journal issue addresses some of the impacts of coal mining that need to be addressed in the decarbonization journey. You will find several papers dealing with coal mine wastes. This is indeed a problem that has been building for years. Tens of millions of tons of coal discard and ultrafine coal are generated each year and stored in discard facilities that require long-term care. Re-purposing and recycling are potential solutions to this ever-growing problem and perhaps the investigations described in this Journal issue will lead to progress in this field. Some of these projects have been or are being funded by Coaltech in the realization by Coaltech members that a just transition requires innovative and sustainable solutions to mining impacts that have been generated over decades.

H. Lodewijks
Coaltech Research Association

The Potential of the Young

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Created: Sunday, 14 August 2022 10:11

Written by P. Pistorius

This volume is similar to previous Student Editions in that it covers a range of diverse topics, from the determination of project readiness in a mining house to the welding behaviour of ferritic stainless steels used to fabricate automotive exhaust systems. There is also significant diversity in the experimental techniques used, and the application of probability calculations is particularly noteworthy in several papers. All this illustrates the breadth, depth, and vitality of the next generation starting to contribute to the activities of the various SAIMM technical communities represented by this Journal. It is worthwhile to remember that these papers have been through the same review process as other papers submitted to the Journal.

The present Student Edition had me wondering where the careers of our students showcasing their work here will take them. How many will return to their respective topics discussed in this edition during their careers, and in what way? What other reunions might our students encounter with previous assignments and experiences they embarked on as their careers progress? These reunions between the past and the present could be unexpected and intriguing. I remembered a few examples from my own career.

My first job, in the mid-eighties, was in a now-defunct heavy foundry that produced mining equipment, such as winders, ball mills, crushers, and a range of dragline components. One of the flagship product lines was winders for the gold and platinum mining industry. Recently, 35 years after leaving the foundry, I helped to evaluate one of those winders. I immediately recognized the imprints from the mould assembly and the indifferent surface finish inherent to the Portland cement-based sand system used in that foundry. The winder did not show any evidence of cracking and was probably good for another three of four decades of service. That the component was completely overdesigned will probably stand the owner in good stead. It is almost counterintuitive, but the scarcity of sophisticated finite-element analyses techniques when this winder was designed will help to ensure a long service life.

Some years ago, I took a group of third-year students on a visit to a power station that was still under construction. We were shown around by the commissioning personnel. It was to me, probably more than to the students, a fascinating visit, with the boilers in various states of construction. We looked down on a low-pressure turbine that was shipped from the supplier as a complete unit and had been lowered into position a few days before our visit. While looking at the casing, I realized that I remembered the patternmaker’s drawings for this component. There was an incident, many decades ago, when a skip filled with chills (small steel inserts used to affect the solidification front) dropped its load through the pattern, destroying months of patternmakers’ work.

I recently helped a mechanical engineer to review the repair procedures for a very large type-316L stainless-steel tank. On working through the documentation, I discovered that the tank was fabricated by a company in Gauteng that I had visited when I started to expand the scope of welding-related activities in the Department of Materials Science and Metallurgical Engineering at the University of Pretoria. The founder and owner of the fabrication company had a very clear and useful perspective on the role that a young engineer should play in such companies: essentially, a young engineer should not spend too much time in the office, get onto the shop floor, and get some holes in his or her overalls. As far as I know, the company has disappeared, but the stainless-steel tank was still in good condition, and it was well worth repairing the few small defects that had developed in over twenty years’ service.
It would be unwise to speculate what circuitous routes the careers of the students represented in these ten papers will follow. The world, Southern Africa, and the mining and metallurgical industries are rapidly evolving, and in this dynamic environment, it is unlikely that most of these papers present first steps in a highly specialized career in the respective fields of knowledge for these students. Rather, it is likely that some of these students will again be acquainted with their work in a roundabout way, possibly similarly to what I have encountered.

From a different perspective, the students’ papers also embody and demonstrate two important skills, namely the ability to absorb and apply new knowledge and the ability to communicate it. These durable skills are only developed when the quality of investigative work and quality of presentation of the results (in this case, as a journal paper) are high. Finally, it is worthwhile to stay somewhat humble, and remember that some students may take the material that they are taught much further than their professors can ever anticipate.

P. Pistorius
University of Pretoria, South Africa

Battery metals – The Next Big Thing?

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Created: Monday, 06 June 2022 15:49

Written by M. Dworzanowski

Mining and metallurgy have been linked throughout time to the development of the human race. You can argue that the First Big Thing was precious metals. Gold and silver have been symbols of wealth since at least Egyptian times. Then the Bronze Age signalled the Second Big Thing, base metals. This started initially with copper and tin to make bronze. Lead was also used during the Bronze Age. Then after this, the Iron Age brought on the Third Big Thing – ferrous metals. Initially this involved only iron. Over time platinum group metals were included with the precious metals and zinc, nickel, and aluminium with the base metals. Ferrous metals have certainly expanded the most via a vast array of alloys, notably steel and stainless steel.

So, what is the Next Big Thing? It has to be battery metals. After the interruption caused by the Covid-19 pandemic, the world has become engulfed by a green revolution. The most prominent aspect of this is rechargeable batteries, especially those for electric vehicles. These batteries require mainly lithium, nickel, cobalt, and manganese. Nickel and manganese were well established within the ferrous metals sector but lithium and cobalt were previously considered minor metals. Now, of course, lithium in particular is viewed as the ’flavour of the month’. Skyrocketing prices of lithium and cobalt in particular have caused an exploration boom, with geologists all over the world looking for lithium and cobalt, amongst many other metals.

From a metallurgical perspective battery metals bring new challenges. All battery metals have to be supplied as very pure salts, usually a minimum of 99.9%, with lithium in the form of carbonate or hydroxide and the others in the form of sulphates. This has resulted in considerable process development research to meet the ever-increasing purity requirements.

The demand for battery metals has had, and will continue to have, an enormous impact on the global mining industry. Geologists, mining engineers, and metallurgists will continue to face greater challenges in the discovery, mining, and processing of battery metals. It is also fair to say that battery metals have really highlighted the contribution of the mining industry to global economic development. And long may this continue!

Developing the South African PGM Industry

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Created: Sunday, 15 May 2022 09:47

Written by H. Möller

South Africa is truly blessed with platinum group metal (PGM) reserves with approximately 90% of the world reserves according to Merchant Research and Consulting. South Africa is a major supplier of the PGMs, namely Pt (74% of world supply), Pd (39%), Rh (82%), Ir (81%), and Ru (90%) in 2021, according to SFA Oxford. These figures are likely to increase depending on the situation in Russia, which is the world’s largest producer of palladium.

Unfortunately, the old Achilles Heel of the South African minerals industry also affects PGMs: the lack of beneficiation and value addition. PGMs are used in a surprisingly wide variety of industrial applications and therefore opportunities exist to better exploit our vast reserves for the benefit of the country.

By far the most widely known industrial application of PGMs (especially Pt, Pd, and Rh) is in auto-catalysts to reduce harmful emissions. However, with the expected decline in the use of internal combustion engines in the near future, there are some concerns for the future of PGMs as industrial materials. The silver lining is that the most likely replacements for internal combustion engines, namely electric vehicles, offer new potential opportunities for PGMs. Indeed, the much-hyped ‘hydrogen economy’ is seen as being of major importance to the PGM industry. PGMs are a key component of electrolysers in hydrogen production and catalysts in fuel cells. South Africa has identified the Hydrogen Economy as being crucial and the Department of Science and Innovation (DSI) recently launched the ‘Hydrogen Society Roadmap for South Africa’. In this roadmap, the important role of PGMs is described in detail.

Apart from catalysts and hydrogen economy applications, PGMs are used in other industrial applications. In order to address the future needs of these applications in South Africa, the DSI has tasked Mintek to prepare a South African Platinum Group Metals Industry Roadmap (SAPGMIR). This forms part of the DSI’s Precious Materials Development Network of the Advanced Materials Initiative.

A survey by stakeholders in the PGM Industry identified the top six applications that should be focussed on for PGM beneficiation in South Africa, namely:

1. Hydrogen Economy (fuel cells, hydrogen production)
2. Catalysts (automotive and other)
3. Batteries (battery storage, solar photovoltaics, lithium sulphur batteries and lithium ion batteries)
4. Recycling (hydrometallurgical or pyrometallurgical processes)
5. Additive manufacturing and powder metallurgy (industrial and jewellery)
6. Medical/biomedical (cancer drugs, neuromodulation devices, pacemakers, diagnostic instruments, catheters, defibrillators, stents, surgical equipment, alloys).

The SAPGMIR is planned to be launched in the next few months and will ensure that the future of PGMs is not only determined by the hydrogen economy.

It is important that all stakeholders embrace these roadmaps to ensure beneficiation and value addition in the South African PGM industry. Government, mining companies, industry players, academia and science councils, and other initiatives such as the OR Tambo Special Economic Zone and The Platinum Incubator (TPI) all have crucial roles to play. Collaboration is the key for catalysing the future of PGMs in South Africa!

H. Möller
Chief Engineer,
Advanced Materials Division, Mintek

From Acronyms to Energy

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Created: Friday, 01 April 2022 08:39

Written by D. Tudor

The first thing that struck me when I read through the abstracts of the papers in this edition was that they are all the work of authors who are based in South Africa. This is a wonderful illustration of the capabilities that exist in South Africa to serve the mining and metallurgical industry.
A wide range of subject matter makes for some challenging reading, with topics that cover artisanal mining, continuous casting in steelmaking, mine design, procurement, exploration drilling, and tailings storage facilities.

I have become increasingly aware of the use of abbreviations and acronyms when reading any technical literature and I illustrate this with information that comes from Drax, a power generating facility near Selby, North Yorkshire, not too far from where I live in the UK.

Drax Power Station (https://www.drax.com) was constructed in the late 1960s and it produces about 6% of the UK’s electricity. It has six boilers, four of which have now been converted to burn biomass instead of coal. The biomass is wood pellets that are sourced from the USA and Canada and shipped to the UK and then railed to the power station. Drax burns in the region of 8 Mt/a of wood pellets.

Drax is the home of the largest decarbonization project in Europe and is now the site of innovation for bioenergy with carbon capture and storage (BECCS), a negative emissions technology essential for fighting the climate crisis.

It was the BECCS acronym that hit me when I looked at the Drax website while I was trying to gain a better understanding of Drax’s biomass operations. I have since been drawn into a state of confusion!

A press release dated 15 December 2021 states that:

• ‘ Drax has approved a further investment in the development of its Yorkshire carbon capture project that will see Worley commence work on the Front-End Engineering and Design (FEED) phase.
• ‘ [The] Contract is part of a 2022 capital investment programme of around £40m that includes site preparation works for BECCS and decommissioning of coal infrastructure following the end of Capacity Market obligations at the end of September 2022
• ‘ BECCS is seen as an essential technology to tackle climate change with the project at Drax set to capture and permanently lock away at least eight million tonnes of CO2 a year ... ’

The UK’s largest power station is looking for a new subsidy. Drax’s £10 billion of subsidies to burn wood for power will come to an end In 2027, and with it Drax’s means of generating profit. In order to continue operating past 2027, Drax plans to build the world’s first bioenergy with carbon capture and storage (BECCS) plant. By capturing the carbon emissions of wood burned for electricity and storing them under the North Sea, Drax intends to generate the negative emissions the UK is reliant upon to reach national climate targets, and would seek to be rewarded for this through new public subsidy.

Drax received more than £800 million in biomass subsidies from the UK government (British taxpayer) in 2020 - with no obvious climate benefit. However, critics suggest that the scientific consensus on ’sustainable’ biomass may soon change.

‘ Recent science demonstrates that burning forest biomass for power is unlikely to be carbon neutral – and there’s a real risk that it’s responsible for significant emissions.’ Ember Chief Operating Officer Phil MacDonald stated. https://ember-climate.org/
‘ Before the government spends more taxpayer money on biomass, we should make sure we know we’re getting the emissions reductions that we’re paying for.’

It would be interesting to see an energy balance that details the energy consumed for the production of the wood pellets plus the energy required to transport, ship, and rail the pellets to Drax. In other words the energy input cost to Drax and compare it to the energy output cost.

It seems to me that the Drax story has a long way to go, and all this because of my interest in an acronym!

D. Tudor

More research and funding needed for mineral processing

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Created: Thursday, 27 January 2022 15:01

Written by Prof A.J.S. (Sam) Spearing

Mining is essential to our life on Earth, but our mineral resources are not renewable and are being depleted rapidly. We will need to recycle more and more minerals and move towards a circular mining economy, in order to meet future demand. This is easy to state but very difficult to achieve in practice, and will need global coordination in a world where we are sadly becoming more polarized and radical.

It is well known that mineable mineral deposits are becoming deeper, more remote, and with lower grades. On the positive side the 4th and 5th Industrial Revolutions will benefit the mining industry the most as we design, build, and operate in ’naturally variable and failed’ material (rock). Real-time monitoring, automation, artificial
intelligence, and robotics will help make mines much safer as people will be removed from the advanced faces, and much more productive. The skills levels required will also increase dramatically as the mining industry will need computer scientists, mechatronic engineers, instrumentation designers, and technicians to name just a few. Cyber-security will become absolutely essential due to the potential dangers of robotic equipment being hacked.

The resolutions and emission goals for 2030 and 2050 proposed at the recent Conference of the Parties (COP 26) in Glasgow, Scotland, while essential for the global environment, will enormously increase the demand for mainly battery minerals such as copper, nickel, lithium, and graphite. No consideration has been given to how these demands will be met, and the lead time for new mines is 5 to 10 years at least.
Considerable research is being undertaken in the fields of ‘green’ and ‘smart’ mining, but I believe that not enough is being done in the field of mineral processing. Specialized metallurgical engineering programmes are being closed globally and absorbed into mainly chemical engineering programmes. This makes financial sense due to low enrolments in metallurgy programmes, but specific and focused courses are essential for at least postgraduate studies and upskilling.

Research areas that I think need more research and implementation include:

• Grade control (geometallurgy) – the benefits can be achieved in the short term and can have an immediate effect on most metal mines. It is strange that few mines have investigated the potential real benefits of this.
• Urban mining – specifically of electronic devices, in which the gold and rare earth grades are higher than most orebodies. This also carries significant environmental benefits.
• Water conservation and protection – reducing fresh water use is essential and can be achieved by more recycling, lower tonnages processed, and the development of less water-intensive processes.
• Dry processing – water is a scarce resource and mining competes with other industries, agriculture, and domestic use. Is an important research field that is not a simple task, but should be an area of research focus due to the massive benefits.
• Energy conservation – mines are traditionally energy-intensive, especially for ore comminution. Efforts must be made to reduce total energy consumption and use more green energy.
• Waste reduction and repurposing on surface – mining produces the largest amount of waste of any industry, and this must be significantly reduced. This can be achieved by maximizing backfilling underground and trying to repurpose the remainder of the waste.

Most of the above are obviously interrelated.

For the mining industry to succeed and help meet the demands of society, more investment into processing is required. International research cooperation is also vital as it tends to generate solutions faster, more efficiently, and at a lower cost.

Prof A.J.S. (Sam) Spearing
School of Mines China University of Mining & Technology

Mine-impacted Water

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Created: Thursday, 11 November 2021 14:58

Written by S. Ndlovu

South Africa has one of the most prominent mining industries in the world. The country saw a boom in the mining industry in the late 19th century with the drivers being gold and diamond mining, followed soon after by coal mining, then PGM processing. Today, gold, PGMs, and coal mining continue to make significant contributions to the economic and social development of the country. Despite the criticality of mining to the growth and development of South Africa and other nations across the globe, the industry is associated with process  challenges and legacies of environmental impact, one of which, is the issue of mine-impacted water.

Mine-impacted water is considered to be one of the main pollutants of surface- and groundwater in many countries that have historical or current mining industries and its potential effects on natural resources, communities, and human health have become increasingly evident. Mine-impacted water has long been regarded as one of the most serious and pervasive challenges facing the mining and minerals industry. While a wide range of technologies are being developed for preventing the generation of, and the control and remediation of, mine-impacted water, most of these approaches consider it a nuisance that needs to be quickly disposed of after minimum required treatment, in line with the legislation of that particular country. However, recently, there has been an emerging paradigm shift towards environmental responsibility and sustainable development. Thus, studies focusing on sustainable treatment technologies, value recovery from the waste solutions, mining closure practices, and legislation to mitigate potential future challenges arising from mine-impacted water have become predominant.

One of the best approaches to dealing with mine-impacted water is to consider it as a valuable resource and look at the recovery of clean water to satisfy the needs of a variety of mining and non-mining users. Since South Africa is a water-scarce country, this is a more practical and applicable approach to the problem. The production of other valuable and saleable by-products such as metals and salts that could be used to offset some of the operational costs is also being considered. In fact, recycling, and re-use of water and the recovery of value products is one of the emerging pragmatic approaches to mitigating the challenges associated with mine-impacted water.

It is at events such as conferences, workshops, and seminars that stakeholders can share unbiased, state-of-the-art expertise and knowledge, novel solutions and approaches, technical knowhow, and advocacy with respect to the legacy of, and sustainable solutions related to, mine-impacted water. Such events can help inspire and accelerate some of the work being done by all interested stakeholders on sustainable and holistic ways to deal with the issue of mine-impacted water. The papers in this edition of the Journal reflect some of the discussions arising from the conference held in November 2020.

The conference, which was organized by the SAIMM in collaboration with the University of the Witwatersrand, Mintek in South Africa, and RWTH Aachen University in Germany, attracted speakers and authors from a number of countries such as South Africa, the UK, Germany, Nigeria, Zambia, Serbia, and Belgium. The idea of the conference was born from a collaborative project between Wits University through the School of Chemical and Metallurgical Engineering and the Institute IME Process Metallurgy and Metal Recycling at RWTH Aachen University, which was sponsored by the National Research Foundation in South Africa and the Federal Ministry of Education and Research (BMBF) in Germany. Since the issue of mine-impacted water is going to be with us for a long time to come, we foresee more such conferences being organized in the future by these well-known higher education and research institutions in collaboration with the SAIMM on a regular basis.

It is my greatest wish that you all enjoy reading the papers in this edition of the Journal, and I hope that you will benefit from some of the ideas presented by the authors.

S. Ndlovu
Professor of Metallurgical and Materials Engineering
DSI/NRF SARChI Chair: Hydrometallurgy and Sustainable Development
School of Chemical and Metallurgical Engineering
University of the Witwatersrand, Johannesburg, South Africa